Magnetic reproducing device with means to prevent accidental erase of record medium



Aprll 29, 1952 5. J. BEGUN 2,594,848

MAGNETIC REPRODUCING DEVICE WITH MEANS TO PREVENT ACCIDENTAL ERASE OF RECORD MEDIUM Flled Dec 12 1950 2 SHEETS-SHEET 1 Q a pzmmmau ,wuzvaoomnmm 9.00% O O INVENTOR. SEMI JOSEPH BEGUN April 29, 1952 s'. J. BEGUN 2,594,848

MAGNETIC REPRODUCING DEVICE WITH MEANS TO PREVENT ACCIDENTAL ERASE OF RECORD MEDIUM Filed Dec. 12, 1950 2 SHEETSSHEET 2 INVENTOR. SEMI JOSEPH BEGUN BY {js ATTORNEY Patented A 29 195 MAGNETIC REPRODUCING DEVICE WITH MEANS TO PREVENT ACCIDENTAL ERASE OF RECORD MEDIUM Semi Joseph Begun, Cleveland Heights, Ohio, as-

signor to The Brush Development Company, Cleveland, Ohio, a corporation of Ohio Application December 12, 1950, Serial No. 200,346

6 Claims. 1 This invention is a continuation-in-part of my application Serial No. 713,963 filed December 4, 1946, for System to Prevent Accidental Rerecord- 'ing on a Magnetic Record, now Patent No.

movable rod extends up through the hollow shaft and terminates adjacent the hub opening in the reel. When this rod is moved, as by placing a reel upon it, the switch in the energizing circuit 2,538,892, issued January 23, 1951. is actuated to change the erasing circuit. For

This invention relates to means for preventing example, actuating means may be connected in the inadvertent erasing of a record which has the hub opening of the reel so that when the reel been recorded on e magnetizable di is placed on the hollow drive shaft, the actuating Among the objects of this invention are novel means causes the movable rod to be depr ss d to magnetic recording and reproducing devices emclose the switch in the energizing circuit, therebodying features which make it impossible to iny to o pl y disconnect the erasing ir i advertently erase a magnetic record which it is O t t Operator cannot inadvertently erase desired to keep intact and free from magnetic the Sign W ic is recorded on the recorded disturbances. m

Another object of the invention is to provide W reference o 1, there is s Wn W a device which may be replaceably connected t spaced-apart reels I0 and II between which there a reel on which is wound a length of recorded is Wound a record um A drive p ta magnetic medium to cooperate with a magnetic I3 is provided and a Spring-biased c p g r r reproducin device to prevent inadvertent erase is adapted to pinch the record. member of t record i 7 against the drive roller l3 to cause the record For a better understanding of the present inmember 12 to be driven in the direction of the vention, together with other and further objects errow- Simultaneously. o r is s p to th thereof, reference is had to the following dereel II o cause e reel II to rotate in a direcscription taken in connection with the accom- H011 to take up the record member s it is panying drawings, and its scope will be pointed driven past the drive roller l3. A more detailed eutin the appended e1eim5 description of the operation of the drive mech- In the drawings; anism may be found in my application Serial No.

Fig. 1 is a schematic view of a magnetic re- 723,735- cording and reproducing device embodying the A recording and reproducing head I5 is located novel means to prevent accidental erasure of the flux linkage relationship with the record record medium; Fig 2 is a sectional View of the ber 12 and suitable circuit means l6 including a device of this invention with the reel in such source Of bias current e p v d for recording d ti th t th record medium may be signals on the record member 12 and suitable reerased at the will of the operator; Fig. 3 is a sec- Producing Circuit means a e provided or p tional view of the device of this invention with ducing the s nals from the record member. As the reel in such condition that the record medium s Well known in t e art the recordingcannot be inadvertently erased; and Fig. 4 is a ing circuits may include many common parts, detailed View of the device which may be onbut the bias section is operative only during renected to the reel in Fig. 2 to prevent the incording. advertent erasure. The terminals I! are the signal output ter- In an aspect of the present invention there is minals and are utilized only during a recording provided for a magnetic recordin and reproducprocess, and the terminals 19 are the signal input ing device a pair of spaced-apart reels at least one terminals and are utilized only during a reproof which has an opening in its hub. A record ducing operation. medium of the wire or tape type is wound on An erasing head 20 is located adjacent the recthe reels. An energizable erase head is provided 0rd member I2 whereby the operator may Seleead acent the record member for erasing the rectively erase the record from the record member ord when the head is energized. Circuit means thereby to condition it to receive and retain a which in lu e a power source and a switch are new record. The erase head zu is energized by connected to the erase head for selectively enter-'5 erase current from the erase current supply gizing the head to erase the record member. means 2| through a circuit which includes an The magnetic recording and reproducing device erase button 22 and a switch 23. Normally the includes means for driving the reel. Part of this switch 23 is closed, as is shown in Fig. 1, so that means comprises a hollow shaft uponwhich the when the operator desires to erase a record on real having the hub opening 15 mounted and a the medium l2 he pushes the erase button 22 3 I thereby completing the circuit from the current supply means 2| through the erase head 29. This energizes the head 29 and establishes an obliterating flux as is well known to the art.

It sometimes happens that the owner of a magnetic recording and reproducing device inadvertently erases or over-records on a record which he meant to keep. This is sometimes done by the operator himself accidentally closing the erase button 22 or accidentally actuating the record control when a desired record is already on the record member in the machine. It may also happen by someone not familiar with the recording and reproducing machine actuating the wrong controls While the machine is running. In order to prevent this accidental erasure, and accidental over-recording there is provided by this invention means which, when properly used, eliminate many chances of accidental spoilage of a desired record. This means comprises a relay I99 energized by alternating or direct currentfrom the erase current supply means 2! or from any other suitable source such as the recording-reproducing amplifier. The relay I99, when energized, opens the switch 23 in the erase current supply circuit and keeps it open until the relay is deenergized. When the switch 23 is opened, the erase button 22 may be pushed without erasing the record member as the circuit from the erase current supply means 2! through the erase head 29 is broken.

When an operator decides that a recording is of sufficient value that he does not want to run the risk of its being erased, he merely connects the actuating device, shown in detail in Fig. 4

and identified by reference character 59, to the reel on which the record member is wound. This actuating device is shown connected to the reel ID in Fig. 3. From then on when the reel is used the erase circuit is automatically broken to prevent accidental erasure.

With the actuating device 59 connected to the reel l9 it is also impossible to record a new record on the prized recording as the relay I99 is also used to break the recording circuit I1 between the circuit I6 and the recording head I5. This circuit break is achieved by utilizing relay N39 to open the switch I8 to prevent either the signal or the bias current from eiiecting a recording on member 12. Thus, with the actuating device 59 in place it is impossible to erase the record on the record member I2 and it is impossible to superimpose a bias current signal or a new record signal on the record member I2.

Fig. 2 shows the reel I9 without the actuating device 59. The reel I9 has a hub portion 39 in which there is an aperture 99. The reel I9 rests upon the rotatable collar or turntable Hand 2. drive pin 49 which is connected to the rotatable collar 39 engages the lower flange of the reel I9 to cause the reel to rotate with the collar 39. A shaft 38 is connected to the rotatable collar 39 and is driven by the belt 99 which is in frictional engagement with a pulley 9I afiixed to the shaft 38. The shaft 38 has a central longitudinal aperture 92 extending through the entire shaft. A movable rod 93 is slidably mounted within the hollow shaft 38 and its upper end terminates adjacent the hub opening aperture 99 in the upper flange of the reel I 9. Slidably mounted on a supporting member 94 directly under the shaft 38 is a follower 95 which is biased upwardly by a spring 9'3. The top of the follower 95 is recessed to accommodate a ball 91 which contacts the rod 93, urging the rod 93 to its higher position where the top of the rod 93 extends above the top of the 4 shaft 38. Immediately below the lower end of the follower a switch 99 is mounted so that in the up-position of the rod 93, switch 98 is open and. when rod 93 is moved downwardly, switch 98 is closed. The switch 98 is in the circuits of the relay I99 so that when switch 99 is open the relay I99 cannot be energized and the erase current supply circuit and the signal recording circuit I? may then be closed by the usual erase and record controls. When the switch 98 is closed, the relay 199 is energized from a suitable power source and the erase head 29 cannot be energized by closing push button 22, nor can a new record be superimposed on the old record, as has previously been described.

When an ordinary reel :9 is put on the rotatable turntable 39, the rod 99 is in its upward position and the operator may erase the record on the medium by pushing the erase button 22, and may make a new record on medium I2. When the operator does not want to undergo the risk of having an unusually good record erased, he connects the actuating device, shown in detail in Fig. 4, to the reel I9. Then, as is shown in Fig. 3, when the reel is placed on the turntable 39, the actuating device 59 causes the movable rod 93 to be depressed thereby closing the switch 98 and energizing the relay 199 to cause switches l8 and 23 to be opened.

Any suitable actuating device may be connected to the reel ID. One suitable device is comprised of a central shaft 5i which fits within the aperture 99 in the hub of the reel [9. At the lower end of the shaft 5i, there are three spacedapart fingers 52 connected to the shaft 5| and at the other end there is an enlarged head portion 53. A curved spring washer 54 is loosely positioned around the shaft 5! between the fingers 52 and the head 53.

As is seen in Fig. 1, the aperture 99 in the hub of the reel I9 includes three radially extending notches 69. When the actuating device 59 is to be connected to the reel I9, the three fingers 52 are aligned with the three notches 99 and the shaft 5| is positioned in the aperture 99. The operator puts his finger on the head 53 and pushes toward the reel I9, causing the spring washer 54 to be flattened and the fingers 52 to pass through the upper flange of the reel id to a location just underneath the flange. The operator then turns the head 53 with respect to the reel I9 to cause the fingers 52 to lie directly underneath the upper flange at a location between the notches 99. The operator then releases the head 53 and the spring washer 54 holds the actuating device in place.

If the operator decides to erase the record, from the record member which is wound on a reel equipped with the actuating device 59, he merely releases the actuating device 59 by pushing down on the head 53 and turning the entire de vice until the three fingers 52 are in registration in the three notches 69 in the reel, at which point the actuating device may be easily lifted away from the reel I 9.

The system shown in Fig. 1 utilizes a switch operated relay I99 for opening switches I8 and 23 in the bias and erase current supply circuits, but it is also within the scope of the invention to use the movable rod 93 to directly open switches I8 and 23 thereby to disconnect the bias and erase current supply sources from the transducer heads I5 and 29.

While there have been described what are at present considered to be the preferred embodiments of this invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention, and it is, therefore, aimed in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of the invention.

What is claimed is:

1. In a magnetic recording-reproducing device: a pair of spaced-apart reels one of which has a hub opening; a recording medium wound on said reels; an energizable transducer head for altering the record on said record member when said transducer head is energized; circuit means including a switch connected to said transducer head for selectively energizing said head in accordance with the position of said switch; means for driving said reels including a hollow shaft upon which said reel having said hub opening is mounted; a movable rod extending up through said hollow shaft and terminating adjacent the hub opening in said reel, said rod upon moving actuating said switch; and actuating means connected to the hub of said reel for closing said hub opening to cause said movable rod to move when said reel is placed on said hollow shaft to actuate said switch.

2. A magnetic recording-reproducing device as set forth in claim 1, further characterized by said transducer head being an erase head, and by said actuating means opening said switch.

3. In a magnetic recording-reproducing device; a pair of spaced-apart reels one of which has a hub opening, a record medium wound on said reels, an energizable transducer head for altering the record on said record member when said transducer head is energized, circuit means including a power source and a switch connected to said transducer head for selectively energizing said transducer head in accordance with the position of said switch, means for driving said reels including a hollow shaft upon which said reel having said hub opening is mounted, a movable rod extending up through said hollow shaft and terminating adjacent the hub opening in said reel, said rod upon moving actuating the switch in said circuit means, and actuating means connected to the hub of said reel for closing said hub opening to cause said movable rod to move when said reel is placed on said hollow shaft to change the position of said switch.

4. A magnetic recording-reproducing device as set forth in claim 3, further characterized by said actuating means including means whereby it is replaceably connectable to said reel.

5. In a magnetic recording-reproducing device; a pair of spaced-apart reels one of which has a hub opening, a record medium wound on said reels, an energizable erase head for erasing the record on said record member when said erase head is energized, circuit means including a power source and a switch connected to said erase head for selectively energizing said erase head in accordance with the position of said switch, means for driving said reels including a hollow shaft upon which said reel having said hub opening is mounted, a movable rod extending up through said hollow shaft and terminating adjacent the hub opening in said reel, said rod upon moving actuating the switch in said circuit means, and actuating means connected to the hub of said reel for closing said hub opening to cause said movable rod to move when said reel is placed on said hollow shaft to change the position of said switch.

6. A reel for a magnetic recording-reproducing device having a reel drive shaft comprising: a hub upon which a magnetizable record member is to be wound, two spaced-apart flange members connected one to either end of said hub and between which said record member is wound, each of said two flange members having a hub opening for receiving said reel drive shaft, and actuating means including means for securing said actuating means in one of said hub openings for closing said hub opening.

SEMI JOSEPH BEGUN.

No references cited. 

